In may well completion operations it is not possible to install a slotted liner at the well intake. In those situations it is common practice to install an unslotted liner in the well, and subsequently perforating the liner using a perforation gun. Such a gun contains a mass of explosives which shoot perforations through fragile spots of the liner. After retrieval of the gun from the well the formation surrounding the perforation may be fractured by pumping a fluid at an elevated pressure through the perforations into the formation.
The conventional perforating and fracturing procedures are time consuming. They also involve the risk that during or after the shooting of perforations well fluids enter the reservoir formation thereby causing formation impairment.
It is an object of the present invention to provide a method and apparatus for perforating a well liner and subsequently fracturing an underground formation surrounding this liner which remedy the above-mentioned drawbacks of the conventional perforation and fracturing procedures.